1. Field of the Invention
The present invention relates to a projector having a light source and an exterior case for accommodating the light source, which modulates a light beam irradiated by the light source and subsequently enlarges and projects the light beam to form a projection image.
2. Description of Related Art
Conventionally, a projector has been used for presentation in a conference, academic seminar, exhibition etc. The projector modulates a light beam irradiated by a light source in accordance with image information to form an optical image, and projects the optical image on a screen etc. in an enlarged manner.
Recently, projectors have come to be used in wider area such as presentation in office meeting and business trip. Further, projectors are now used in technical review session in research and development section by fetching and projecting CAD/CAM/CAE data, various seminars and workshops, and school classroom during audio-visual education. Further, projectors are used for reviewing remedy and medical guidance by projecting medical image and data such as CT scan and MRI and for effectively staging exhibitions and events attracting a lot of people.
Some of such projectors are known to have a light source and an exterior case for accommodating the light source, which modulates a light beam irradiated by the light source and subsequently enlarges and projects the light beam to form a projection image.
An opening is formed on the projector corresponding to the position of the light source for taking out and exchanging the light source when the life of the light source is expired. Ordinarily, such opening is closed with a lamp cover attachably/detachably provided to the exterior case, which can be detached from the exterior case in exchanging the light source.
The lamp cover is usually attached to the exterior case with a screw. Though such screw-fitting type is extremely simple in its attachment structure, a troublesome work of unscrewing a plurality of screws is required for detaching the lamp cover from the exterior case.
On the other hand, in some arrangements, the lamp cover is provided on the top surface of the exterior case and is attachable/detachable to the exterior case by being slid along the top surface. In such slide type, a slide guide is formed on the exterior case for slidably supporting the lamp cover, so that it is not necessary to turn a multiple of screws. However, in order to slidably open and close the lamp cover, an anti slip or a notch (similar to anti slip or notch formed on cell cover of a table clock or a remote controller) has to be formed on the surface of the lamp cover, which worsens appearance thereof.
An object of the present invention is to provide a projector capable of improving workability for exchanging a light source and appearance thereof.
On the other hand, the above-described lamp cover is usually attached to the bottom surface of the exterior case.
However, when the lamp cover is disposed on the bottom surface of the exterior case, the projector has to be turned upside down in exchanging the light source. Accordingly, after completion of exchanging work, the attitude of the projector relative to a screen has to be re-adjusted and exchanging work becomes so troublesome.
Especially, when the projector is used in audio-visual room etc., the projector is often installed on ceiling in a manner that the ceiling surface and the bottom side of the exterior case are opposed. Accordingly, the projector has to be once detached from the ceiling in order to exchange the light source, thereby making exchange work so troublesome.
On the other hand, some of the lamp cover is disposed from top surface to a side of a projector.
According to such arrangement, though the light source can be easily exchanged, the attachment structure of the lamp cover can interfere with the other arrangement. Specifically, for instance, in slide type, the surface of the exterior case has to be cut to form a guide for a lamp cover to be slid. When such guide is formed continuously along the surface of the exterior case, the guide can interfere with the other components disposed on the side of the exterior case (such as an exhaust hole for discharging exhaust air from a cooling fan toward the outside and a handle used for carrying the projector), thereby lowering freedom of design.
Another object of the present invention is to provide a projector capable of facilitating exchange work of a light source and improving freedom of design.
A projector according to an aspect of the present invention has a light source and an exterior case that accommodates the light source, the projector modulating, enlarging and projecting a light beam irradiated by the light source to form a projection image, the projector including: an opening formed on the exterior case at a position corresponding to the light source; a slidable lamp cover that closes the opening, the lamp cover being capable of being attached to and detached from the exterior case; a first biasing mechanism that biases the lamp cover along slide direction thereof toward outside of the exterior case; an engagement structure that fixes the lamp cover to the exterior case; and an operating portion that is operated to release engagement of the engagement structure by being operated.
According to the above aspect of the present invention, when the operating portion is operated to release the engagement of the lamp cover with the exterior case, the lamp cover is slid along the slide direction toward outside of the exterior case by the first biasing mechanism, thereby unfixing the lamp cover from the exterior case.
Therefore, unlike conventional screw-fitting, the lamp cover can be unfixed from the exterior case with one action of operating the operating portion for detaching the lamp cover from the exterior case, workability can be improved in exchanging the light source. The operating portion is not restricted to the operation switch etc. but may be arranged in different manner as long as the engagement of the lamp cover with the exterior case can be released.
Since the lamp cover is slid toward outside of the exterior case by the first biasing mechanism when the engagement is released, anti-slip, notch etc. for an operator to slide the lamp cover by hand is not required on the surface of the lamp cover, thereby improving appearance thereof.
In the projector of the present invention, the lamp cover may preferably be disposed on a top surface of the exterior case.
In the conventional arrangement, the lamp cover is usually disposed on the bottom side of the exterior case and the projector has to be turned upside down in order to detach the lamp cover. Accordingly, the attitude of the projector relative to a screen has to be re-adjusted after detaching the lamp cover and completing exchange work of the light source, so that exchange work can be troublesome. Especially, when a projector is used in an audio-visual room etc., the projector is often attached on ceiling with the ceiling surface and the bottom side of the exterior case being opposed. Accordingly, in order to exchange the light source, the projector has to be once detached from the ceiling before exchanging work, thus making the work very troublesome.
In the present invention, since the lamp cover is disposed on the top surface of the exterior case, when the light source is exchanged, exchange work can be conducted while the top surface of the projector is facing upward (i.e. in an ordinary attitude for a projector to be used in, for instance, installing the projector on a table) and it is not necessary to turn the projector upside down. Accordingly, re-adjustment of the attitude and position of the projector is not necessary after exchanging the light source, thereby further enhancing the workability in exchanging the light source.
Further, when the projector is attached on a ceiling, the lamp cover can be detached from the top surface facing downward, so that it is not necessary to detach the projector from the ceiling, thus further facilitating exchange work of the light source.
In the projector according to the present invention, the first biasing mechanism may preferably be formed by a part of an elastically deformable shield plate provided in the exterior case.
According to the above arrangement, since an independent component for constructing the first biasing mechanism is not necessary, the number of components can be reduced.
In the projector according to the present invention, a detector that detects attachment/detachment of the lamp cover to the exterior case may preferably be provided on the exterior case, the detector having a detection switch biased toward the lamp cover that is actuated being pressed by the lamp cover in a direction approximately opposite to biased direction thereof, the detector determining attachment/detachment of the lamp cover to the exterior case based on whether the detection switch is pressed by the lamp cover for a predetermined amount or not, and the first biasing mechanism may preferably also work as the detection switch of the detector.
Accordingly, since the first biasing mechanism is constructed using the detection switch of the detector, an independent component for constructing the first biasing mechanism is not necessary, so that the number of components can be reduced.
The first biasing mechanism may be composed only of the detection switch of the detector, may be composed only of a part of the shield plate, or may be composed of both of the elastic member of the detector and a part of the shield plate.
The means for biasing the detection switch to the lamp cover may be a means for biasing the detection switch by an elastic member formed of a spring, rubber etc., or the detection switch itself may be formed by an elastically deformable member and the force for returning to original shape may be used as the biasing force.
In the projector of the present invention, a shield covering an inner surface of the lamp cover may preferably be provided on the lamp cover, the shield being electrically conducted with a shield provided in the exterior case.
Accordingly, since the shield on the inner surface of the lamp cover and the shield in the exterior case are electrically conducted, the electric potential of the shields can be maintained equal, so that leakage of electromagnetic noise toward outside can be securely prevented.
Further, since the shield is provided on the inner surface of the lamp cover, heat radiation efficiency of the lamp cover can be enhanced and thermal deformation of the lamp cover can be prevented.
In the projector of the present invention, the engagement structure may preferably be located inside the exterior case.
According to the above arrangement, since the engagement structure between the lamp cover and the exterior case is disposed inside the exterior case, the engagement structure is not exposed to the outside, thereby improving appearance.
In the projector of the present invention, the operating portion may preferably be disposed at a position recessed toward inside of the exterior case.
Since the operating portion is disposed at a position recessed toward inside of the exterior case, erroneous touch on the operating portion to operate the operating portion in carrying and operating the projector can be prevented, thereby preventing unexpected fall-off of the lamp cover by erroneous operation.
In the projector of the present invention, a slide portion capable of sliding in the slide direction relative to the exterior case may preferably be formed on the lamp cover, a guide in slide contact with the slide of the lamp cover may preferably be formed at a periphery of the opening of the exterior case along the slide direction, a notch may preferably be formed in the intermediary of the guide of the exterior case, and the slide of the lamp cover may preferably be capable of being fitted into and detached from the exterior case.
Since the notch is formed in the intermediary of the guide and the slide of the lamp cover is capable of being fitted to and detached from the exterior case from the notch, the slide of the lamp cover can be fitted to and detached from the exterior case on the way of slide movement of the lamp cover relative to the exterior case, i.e. when the slide reaches the notch of the guide in attaching and detaching the lamp cover. Accordingly, the distance for the lamp cover to slide relative to the exterior case can be shortened, and the lamp cover can be attached and detached even when the projector is installed in a narrow space.
In the projector of the present invention, a second biasing mechanism that biases the lamp cover in a direction to be away from the exterior case along attaching and detaching direction of the slide may preferably be provided.
Accordingly, when the lamp cover is slid to reach the notch of the guide in detaching the lamp cover, the lamp cover is biased in a direction away from the exterior case by the second biasing mechanism, so that the slide of the lamp cover is detached from the guide of the exterior case, thereby facilitating attachment and detachment of the lamp cover.
In the projector of the present invention, the second biasing mechanism may preferably be formed by a part of elastically deformable shield plate provided in the exterior case and/or a part of elastically deformable shield plate covering an inner surface of the lamp cover.
According to the above arrangement, since the second biasing mechanism is composed of a part of shield plate provided in the exterior case and/or a part of shield plate covering an inner surface of the lamp cover, an independent component for constructing the second biasing mechanism is not necessary, so that the number of components can be reduced.
A projector according to another aspect of the present invention has a light source and an exterior case that accommodates the light source, the projector modulating, enlarging and projecting a light beam irradiated by the light source to form a projection image, the projector further including: an opening formed only on a top surface of the exterior case at a position corresponding to the light source; and a lamp cover that closes the opening, the lamp cover disposed only on the top surface of the exterior case and capable of being attached to and detached from the exterior case.
In the present invention, since the lamp cover is disposed on the top surface of the exterior case, when the light source is exchanged, exchange work can be conducted while the top surface of the projector is facing upward (i.e. in an attitude for a projector to be used such as installing the projector on a table) and it is not necessary to turn the projector upside down. Accordingly, re-adjustment of the attitude and position of the projector is not necessary after exchanging the light source, thereby further enhancing the workability in exchanging the light source.
Further, when the projector is attached on a ceiling, the lamp cover can be detached from the top surface facing downward, so that it is not necessary to detach the projector from the ceiling, thus further facilitating exchange work of the light source.
Since the lamp cover is disposed only on the top surface of the exterior case, the lamp cover does not interfere with the other components disposed on a side of the exterior case (such as exhaust hole for discharging exhaust from the cooling fan toward outside and a handle used for carrying the projector), so that freedom of design can be improved.
Further, since the lamp cover is disposed only on the top surface of the exterior case and is not extended to a side of the exterior case, the appearance can be improved.
In the projector of the present invention, an engagement structure that engages the lamp cover with the exterior case to attach the lamp cover to the exterior case and an operating portion that is operated to release the engagement structure may preferably be provided.
In a conventional projector, the lamp cover is usually screwed to the exterior case. Accordingly, in order to detach the lamp cover from the exterior case, a plurality of screws has to be unscrewed, which is very troublesome.
In the projector of the present invention, since the lamp cover is attached to the exterior case by the engagement structure and the operating portion for releasing the engagement structure is provided, the engagement of the lamp cover can be released by operating the operating portion. In other words, since the lamp cover can be detached from the exterior case with one touch, exchange work of the light source can be further facilitated.
In the projector of the present invention, the engagement structure may preferably be disposed inside the exterior case, and the operating portion may preferably be disposed away from the lamp cover.
Since the engagement structure of the lamp cover and the exterior case is disposed inside the exterior case and the operating portion is disposed away from the lamp cover, notch etc. for forming the engagement structure and the operating portion is not necessarily formed on the outer surface of the lamp cover exposed to the outside. Accordingly, the gap between the outer surface of the lamp cover exposed to the outside and the outer surface of the exterior case can be minimized, thus preventing light leakage of the light source from the gap and improving appearance.
In the projector of the present invention, the operating portion may preferably be disposed at a position recessed toward inside of the exterior case.
Since the operating portion is disposed at a position recessed toward inside of the exterior case, erroneous touch on the operating portion to operate the operating portion in carrying and operating the projector can be prevented, thereby preventing unexpected fall-off of the lamp cover by erroneous operation. Incidentally, the operating portion may not be the operation switch but may be arranged in other way as long as the engagement between the lamp cover and the exterior case can be released.
In the projector of the present invention, the engagement structure that engages the lamp cover with the exterior case may preferably be provided on the lamp cover, the engagement structure including a first engagement portion and a second engagement portion inserted and engaged with the exterior case, and the first engagement portion may preferably be inserted to the exterior case along a direction approximately parallel to the top surface and the second engagement portion may preferably be inserted to the exterior case along a direction approximately orthogonal with the top surface.
Since the first engagement portion and the second engagement portion inserted to the exterior in mutually different direction are provided to the lamp cover, detachment of the lamp cover from the exterior case becomes unlikely, thus securing attachment of the lamp cover to the exterior case.
In the projector of the present invention, a first biasing mechanism that biases the lamp cover in a direction opposite to inserting direction toward the exterior case of the second engagement portion of the lamp cover may preferably be provided.
Since the first biasing mechanism for biasing the lamp cover in a direction for the second engagement portions to be detached from the exterior case is provided, the second engagement portion can be pushed in a direction to be pulled out from the exterior case in accordance with releasing the engagement of the second engagement portion by the operating portion, so that the lamp cover can be easily detached from the exterior case, thereby facilitating detachment of the lamp cover.
In the projector of the present invention, shields respectively covering inner surface of the exterior case and inner surface of the lamp cover may preferably be provided, the first biasing mechanism may preferably be made of metal, and an end of the first biasing mechanism may preferably be in contact with the shield covering the inner surface of the exterior case and the other end may preferably be in contact with the shield covering the inner surface of the lamp cover when the lamp cover is attached to the exterior case.
Since the shield for covering the inner surface of the exterior case and the shield for covering the inner surface of the lamp cover are provided and the shield are electrically conducted by the first biasing mechanism, leakage of electromagnetic noise from the inside of the exterior case toward outside can be prevented.
Further, since the first biasing mechanism works both for biasing the lamp cover in a predetermined direction and for electrically connecting the shields, the number of components can be reduced.
In the projector of the present invention, a second biasing mechanism that biases the lamp cover in an inserting direction toward the exterior case of the first engagement portion of the lamp cover may preferably be provided.
According to the above arrangement, since the second biasing mechanism for biasing the lamp cover in a direction for the first engagement portion to be inserted to the exterior case is provided, the first engagement portion is not fallen off from the exterior case even when the engagement of the second engagement portion is released by the operating portion. Accordingly, the lamp cover is not detached simultaneously with releasing the engagement of the lamp cover, so that damage on the lamp cover caused by fall-off can be prevented when the projector is installed on a ceiling.
In the projector of the present invention, the lamp cover may preferably have an engagement portion for engaging the lamp cover with the exterior case while the lamp cover is slightly opened.
According to the above arrangement, since the slightly-opened condition of the lamp cover can be maintained by the engagement portion, the lamp cover is not detached simultaneously with releasing engagement of the lamp cover by the operating portion. Therefore, when the projector is attached on a ceiling, the fall-off of the lamp cover simultaneously with operation of the operating portion in detaching the lamp cover can be prevented, thereby preventing damage on the lamp cover by fall-off.
In the projector according to the present invention, a detector that detects attachment/detachment of the lamp cover to the exterior case may preferably be provided to the exterior case, and the detector may preferably be operated by the engagement portion of the lamp cover.
Since the detector for detecting attachment/detachment of the lamp cover to the exterior case is provided and the operation of the detector is conducted by the engagement portion of the lamp cover, it is not necessary to provide an independent component for operating the detector on the lamp cover, thereby reducing the number of the components. Further, since the detector for detecting attachment/detachment of the lamp cover to the exterior case is provided, attachment failure etc. of the lamp cover to the exterior case can be prevented.